xtset ccode year

xtreg fpi  shared_ideol lula1##shared_ideol lula2##shared_ideol dilma##shared_ideol   , r
estimates store one
xtreg fpi  shared_ideol lula1##shared_ideol lula2##shared_ideol dilma##shared_ideol dom_percent global_south   , r
estimates store two
xtreg fpi  shared_ideol lula1##shared_ideol lula2##shared_ideol dilma##shared_ideol dom_percent global_south  unga_usa , r
estimates store three
xtreg fpi  shared_ideol lula1##shared_ideol lula2##shared_ideol dilma##shared_ideol dom_percent global_south unga_usa i.year , r
estimates store four
xtreg fpi  shared_ideol lula1##shared_ideol lula2##shared_ideol dilma##shared_ideol dom_percent global_south unga_usa i.year i.region_n , r
estimates store five

esttab one two three four five, r2
